Capped contact met



Mar. 13, 1923.

E-RLOCHMAN. PROPELLER. HLED ocr. 19. Isis.

4 SHEETS-,SHEET I.

E.R. LOCHMAN.

Mar. 1s, 1923.

4 SHEETS-SHEET 3.

s HHH H H|||||||||n ...ILUIVH n Hw u n H UAM Mar. 13, 1923. 1,447,994.

E. R. LOCHMAN.

PROEELLER.

FILED OCT'. l9. 1918. 4 SHEETS-SHEET 4 @atented Nov.1 v 39 g narranstares Param'- orrrca WILLIM J. GAGNON, 0F BRIDGEPORT, CONNECTICUT;ASSIGNOR T0 THE BEAD CHAIN MANUFACTURING COMPANY, F BBIDGEPORT,CONNECTICUT, A CORPORATION OF CONNECTICUT Application filed April Q5,

This invention has to do with a contact pin of the type having a capover its inner or attaching end, as described in my copendingapplication 4Serial No. 305,296 filed September 11, 1928. The presentinvention is an improvement on the pin there described in that it doesaway with the need of making an anchorage shoulder on the mainbody ofthe pin, and yet provides such a shoulder in a simpler way, that is, byHanging the cap at its open end.

A pin made in accordance with this invention is described hereinafterwith reference to the accompanying drawings .in which,

Figure 1 is a view in central vertical seetion through a anged cap.

Figure 2 is a view in elevation of a pin made to receive that cap, and

Figure 3 is a view in elevation of the pin with the cap in place, thecap being shown in section.

The pin shown here is made of sheet metal in tubular form with alongitudinal seam 11. At its lower end'12 the wall of the `pin is drawnin to decrease the size of the )opening and thus to facilitate thesoldering head, is necked down so that there is an inwardly taperedportion ending at an annular shoulder 16. 'The latter presents a.surface that is substantially at right angles to the axis of the pin.The material of the pin is turned in at the top giving an end wall 17with a hole 18 in it.

. The cap 20 is made from sheet metal in the form of a cup with anannular flange 21, substantially at right angles to its' axis, at itsopen end. If the cap is pre-formed with a flange, then to attach it tothe pin, the cap is placed over the tapered headof the pin until its endwall 22 rests against the top wall 17 and then it is clinched againstthe sides of the tapered head in any 4suitable way to produce a secureunion. The flange 21 is notdisturbed, the eect of the compression beingnarran contraer rm me. serial m, aereas.

onlyto bring the base of the flange in upon the shoulder 1,6.

For quantity production it is preferable not to pre-form the flange butto start with simpl a cup, of greater depth however than that esired forthe final flanged cap. Such a cup is fed to a die containing the pinvand having an inwardly. tapered portion around the head of the pin. Asthe cup advances into this portion and into position over the head ofthe pin its side wall is necked down to bring it against the sides ofthe pin. There should be an annular shoulder op osite the shoulder 16 ofthe pin to engage t e rim of the cup and flare it as it advances untilthe end Wall of the" cup comesagainst the end wall of the pin. Theresult is a flanged cap clinched against the tapered head of the pin.The pin is designed especially for being molded into a base by themethod (set forth in my copending applications, Serial No. 56,- 292,filedSeptember 14. 1925, and Serial No. 202,082 filed June 28, 1927)which involves the shaping of the base material about the heads of thepins while simultaneously opening a wireway to the interior of the pin.The capped pins are set upin recesses in the lixed die with the taperedhead portions, above the flanges 21, extending into the mold cavity. Thebasematerial is put in around the heads and then the forming die, whichis provided with conical projections registering with the pins, isbrought down to press the f v material into shape. In the course of theshaping, the conical proj eetions pushthrough the base material andpierce the end walls 22 of the caps on the pins which theretofore haveexcluded the base material from the interiors of the pins. Thus thewireways are.`

, ping these slotted portions togetherso that the slotted end'portionl28 of one Ablade overwithout breaking. Filler pieces 30, 31, 32 andv 33are then joined and glued to the hub portion of the propeller blank withtheir grain and straight surface jointscrunning lengthwise with theblades, so that the hub of the propeller now forms a solid mass of woodwith its grain, excepting the laminations B, running lengthwise with thepropeller blades. These filler pieces also extend a considerabledistance beyond the hub and they are roughly .out into the outline asshown in Fig. 1, andthe pointed ends 34 and35 'reach to about one-halfof the length of thel respective blades whereby the blades arereinforced and held in their proper sha e.

` It is to he understood that any number of laminations may be used foreach blade or each may be formed out of one plank `and joined togetherlin 'the manner previously described so that,`while l' prefer theconstruction just described,l l do not limit'rm'y invention to bladeshaving three laminations. A The fully prepared blank, as shown in Fig. 1is then shaped and finished-.off into its completed form.

Referring now to Figs. S'to 14 inclusive, l' have shown certainimprovements onthe construction previously described, though the generalmethod of constructing the propeller is the same. ln this form eachblade 27 is formed of three laminations A', B and C as before with thegrain of the Wood of these'laminations disposed as previously describedso that the grain of' laminations'A and C" run lengthwise ofthe bladeand that of lamination 'B' running rearward and outwardl from theleading edge 36 to the .trailin edge 37 of the blade. The laminationsA', and C are not, howL ever, of uniform width but tapered from theirinner ends toward the tip of the blade as clearly shown in Fig. 9. Eachlamination is treated with steam and then has its outer portion 38pressed into the proper yrelatively varying'screw pitch form after whichthe laminations are glued together, set and dried and are then joined aspreviously describedby means of the slots 3,9 similar to the slots 27ofthe previously described construction so as to give the blades theproper general pitch. To lfirmly interlock the blades together, awedge40 is used for each slotted4 portion of the joint, said` l46 areconnected together in the following manner:

hrThe blades have key ways 47jcut in them' at a slight angle as shown inFigs. 8 to 10 inclusive and the end filler pieces 41 and 42 have similarkeyways 48 cut therein and adapted to register with the keyw'ays 47 intheblades, F ig. 14 showing a general view of the end piece 41.l Theseend filler pieces are then secured to the blades by means of keys 49,the piece 41 being first glued and keyed as shown in Figs. 12 and 13 andthe piece 42 being then 'glued and keyed as shown so that its inner edgeabuts against the piece 4l and the filler pieces 45 are then joined andglued to the pieces 41'and 42. The grain of wood of the pieces 41, 42and 45 runs lengthwise with the blades.

The blades have ke ways 50 cut in them vice particularly inthe navalWork it is necessary to reinforce and protect the tip of the ropelleragainst sand and pebbles and while a brass tip is usual in the presentinstance l provide a special construction for .receiving the brass tip54 in that the trailing edge of the blade adjacent the tip is p rovldedwith a wooden tip plate 55 whose gain uns at an angle to that of thegrain o 56 is thick to reinforce the tip edge. The tip 54 is secured tothe blade by screws 57 and rivets 58 and is provided with vent holes 59.j

Referring to Figs. 18 to 24 inclusive l hereshow various methods foradditionally keying the parts together adjacent the hub of the propellershown in F ig. 11. In Fig. 21 I show a peculiar form of key 60 havingcorrugated sides and this is drivenA into the propeller adjacent the-hubas shown in-lig.

18, the key seat being formed by drillingl the laminations A and whoseouter edge f have a wooden IVoodruff key 61 and in Fig; 18 I show howthese keys are used While Figs. 19 and 20 showsectional 'views with ,thekeys 60 and 61 in place.

first key and this keying may be arranged in rowsfsothat the lower endof a key'in one row engages the lower ends of spaced apart keys in theadjacent row as the key 62c which at its lower end extends through apart of the lower'ends of the keys 62 and 62d thereby forming aconstruction in which the keys are firmly interlocked.`

In both of the forms of the propeller holes i 63 are drilled through thehub to receive the bolts for securing the metal hub plates .to thepropeller and since the blades are at anfangle to each other the boltsinser'ted in these holes will pass through the hub portions of bothblades which of course produce a strong construction.

. tions of the blade.

One of the'important features of the constructlon shown in Figs. 8 to 11 inclusive is the use of the inner lamination B which due to thedisposition of the grain at an angle to that of the other laminationsgreatly strengthens lthe propeller so that it will withstand thetwisting strain against the blade brought 4about by the thrust and sothat it will withstand the centrifugal strain due to the centrifugalforceset up in the rapidly revolving blades and the tapering of thislamination is such as to properly take care of these strains at thevarious sec- As will be apparent in Figs. 9 and 10 the inner laminationB is tapered the most, andsaid lamination being formed and' bent intoits proper shape to form the blade in the rough and it will be readilyseen that the final forming of the blade will not affect the thicknessor the rela-l tive screw pitch of said lamination B as all the/finishingis done on the outer laminations A and C.

I prefer to use a wood of tougher fibre for the, inner lamination B asit greatly strengthens the blade t'iresist the twigsting strain whichordinarily causes a flutter of the propeller and in practice I usemahogany for the outer lam'inationsA and C and tougher wood as walnutfor the inner lamination B. l

When the ordinary blade is provided with a brass tip which is usuallysecure to the propeller by screws, it. has been found in practice thatthe straight grain of the wood at the tip is not strong enough to holdthe brass tip against the splitting of the tip of the propeller and theloosening of the tip byreason of the centrifugal force acting l'upon thebrass tip and tending to move itI and the fastening screws away from thepropeller, with the result that the screws will be torn out ,of theblade tips and will tend to split the ends of the bade. Referring now toFigs. 15 to 17 inclusiv'e, it will be noted that these disadvantagesabove pointed tips of the blades of wooden laminations with A'the grainsof the wood running at angles to each other so that when the fasteningscrews for the brass tips are secured within the tips of the blades theywill be firmly held in place and will not tend to split or tear the`blade because the cross grain laminations hold them firmly againstmovement. It will be noted that the laminations out have been overcomeby constructing the are laid parallel with the surface of the propellerblade so that all or most of the screws reach into or through thecentral lamination B. \Vhat I claim as my invention is: 1. A propellerhaving two blades, each blade having laminations extending the width andlength of the blade and vsecured together, each of said bladeshaving'slotted inner ends joined together at an angle forming thegeneral pitch of said propeller.

2. A'propeller having two blades, each blade having a centrally disposedlengthwise` extending slot at the hub end portion thereof, said slottedends interlocking with each other at an angle to form the pitch of saidpropeller.

3. A propeller comprising a pairv of separate blades, each of saidblades having slotted inner ends, said slotted ends interlocking witheach other at an angle formingthe'pitch of the blade, and filler piecessecured to the blades4 at the hub and extending beyond the hub toreinforce the blades.

4.v A propeller comprising a pair of separate blades, each bladetapering lengthwise from its hub end to its tip, each blade having aninclined lengthwise extending slot, said. slotted ends engaging eachother at an angle to form the pitch of the propeller and wedges securingthe slotted ends of the blades together.

5. A. propeller comprising a pair of sepaf rate blades, each bladetapering lengthwise from its hub end to its tip, means for securingsaid. blades together at the hub at an angle to eac-h' other to formthefpitch of the propeller, and filler ieces secured in the puter recessformed y the blades at the lub.

6. A propeller comprising a pair of separate blades, each bladeconsisting of a plurality of laminations extending the length and widthof the bla-de, means for joining said blades together in overlappingrelation at the hub, filler pieces, and means for keying the fillerpieces to the blades adjacent the hub.

7. A propeller comprisimgr a pair of separate blades, means for joiningthe blades together, said blades having keyways therein adjacent, fillerpieces provided with keyways registering: with the keyways of theblades, keys in said keyways securing the filler pieces to the blades,and other filler pieces Secured to the first named filler pieces.

8. A propeller comprising a pair of separate blades, means for joiningrthe blades together at an angle to each other at their hub ends, eachblade at its hub end havingr a longitudinally extending slot, saidslottedends interlockin,f r with each other and haV- img aperturestherein passing through the hub portions of'both `blades to receiveIthe. bolts clamping,r the propeller to the driving' shaft.

9. A propeller comprising two blades and a plurality of illervpieces,means for joining the vblades together at their hub ends, means forsecuring the filler pieces to the blades where they are joined together,said blades and filler pieces having apertures therein extending,rthrough the hub portions of both of said Iblades and through said fillerpieces to receive, the bolts clamping @the propeller between the flangesof its drivingr shaft.

10. A` propeller comprising a pair of blades, means for joining theblades together at their hub ends, filler pieces secured to the bladesWhere they are joined together,

and keys passing through said filler pieces and into said blades.`

11. A propeller comprising a pair of blades. means for joining theblades together at their hub ends, filler pieces secured to the bladeswhere they are joined together, and .n

keys passing through said filter pieces and into the blades andinterlocking with'each other.

12. In a propeller, the combination of a pair of separate blade-s andmeans for joining the inner ends of said blades together in cross-wiseoverlappingr relation at and beyond the hub. L l

j 13. A propeller blade co1 nprisin, r a rentral 'lamination and twoouter laminations,

said -central lamination being: proportion-y and its thinner part to thetip section ofv the blade. A

15.Apropeller comprising,r a pair of blades, said blades being taperedand pro# vided With slots at their hub sections, and wedges for saidslots to interlock said blades.

In testimony whereof, I afix my signature.

EMIL R. LOCHMAN.

